DESIGNATED WORK: Nick Johnson spent two days in Arizona last week with Yankees hitting coach Kevin Long working on the designated hitter's feet while standing in the batter's box. Photo: Getty Images

Nick Johnson may have two of the slowest legs in The Bronx this summer, but Kevin Long isn’t interested in the Yankees’ designated hitter’s foot speed.

Instead, the hitting coach is focused on Johnson using the lower half of his body to keep from getting beat on inside pitches.

Long believes even if the left-handed hitting Johnson doesn’t attempt to become a dead-pull hitter — something Johnson says won’t happen intentionally — the jet stream that flows to right field and Yankee Stadium’s short porch will result in Johnson’s home run totals rising.

Johnson went to Arizona last week for a two-day session with Long and the batting cage rat immediately went to work on Johnson’s feet.

“We worked on trying to keep his back foot [left] in place, trying to keep it from flying back,” Long said of Johnson’s approach. “When it moves he collapses the inside right away. That takes away the inside of the plate. We talked about Yankee Stadium and figured we might want to address that.”

Like Curtis Granderson, who essentially replaces the popular Johnny Damon, Johnson is taking over for Hideki Matsui and will be under the microscope as the DH. The classy Matsui spent productive years with the Yankees and his final act was winning the World Series MVP last season. And there were the 28 homers and 90 RBIs.

A third-round pick of the Yankees in 1996, the oft-injured 31-year-old Johnson played in 248 games for the team from 2001-03 at first base. He split for Montreal in a trade for Javier Vazquez after the 2003 season, played for the Expos, Nationals and Marlins and returns to The Bronx looking to work with Long, who tutored Nick Swisher, Alex Rodriguez and Granderson this offseason.

Johnson missed the entire 2000 season with a strained muscle in the right hand. He was limited to 96 games in 2003 because of a stress fracture in the right hand, 73 games in 2004 thanks to a fractured right cheekbone and was out the entire 2007 season because of a fractured right femur suffered at the end of 2006. In 2008, Johnson was limited to 38 games due to a right wrist problem and spent a month on the disabled list last season due to a strained right hamstring.

“I never used my legs in the past,” the career .273 hitter with a .402 on-base percentage said. “It felt good to work on that.”

Known for a keen eye and the ability to lay off pitches, Johnson and Long also talked about the patient Johnson attacking a bit more.

“Being ready to hit from pitch one and staying more aggressive,” Johnson said of Long’s message.

So, will Johnson be seduced by the short right field porch and the mechanical change in his feet that will allow him to get to inside pitches? In three games at Yankee Stadium last June, Johnson went 1-for-10 and hit three balls to the right side — all grounders.

“You see how the ball flies out of there but I really can’t get locked into pull,” Johnson said. “If I do I get messed up. I try to stay in the middle of the field.”

Johnson, whose career-high homer total was 23 in 2006 with the Nationals, has been looking at tapes Long gave him to watch hitters work their lower half. Last year Eric Hinske credited Long for working on his legs that led to more drive.